8x00 family of Disk Arrays 4.02.00 Installation and Reference Guide

5. Follow the on-screen instructions and reboot the system for the new registry parameter to take

effect.

IMPORTANT:

During the process of enabling or disabling of load balance in an MSCS environment (for a cluster

with more than two nodes), you may have a set of nodes using SCSI-3 persistent reservations along

with another set of nodes using SCSI-2 reservations. In such cases (as part of step 1 in the above

sections), HP recommends that you move the cluster resources to the set of nodes that has the majority

reservation.

NOTE:

Once all the nodes in the cluster have the support for load balancing in MSCS enabled, you can

change the load-balancing policy for the cluster devices using the HP DSM CLI or HP MPIO DSM

manager.

Recovering inaccessible disk devices

If there is a stray reservation on a disk device, the device becomes inaccessible to the host systems

connected to it. This is because the strong reservation type (persistent reservations), supports load

balancing in clusters.

You can use the persistent reservations clear utility that comes with the HP MPIO EVA DSM package

to remove the stray reservations. For more information on how to use this utility, see HP MPIO EVA

DSM persistent reservations clear utility.

HP MPIO Full Featured DSM for P6x00 family of Disk Arrays 4.02.00 installation and reference

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